To reach Wilmington Porter Reservoir, De in this distance one would set out from Prairie Du Chien, Wi bearing 99.9° or E and follow the great circles arc to approach Wilmington Porter Reservoir, De bearing 110&deg or ESE .

Wilmington Porter Reservoir, De has a humid subtropical climate (Cfa) whereas Prairie Du Chien, Wi has a hot summer continental climate with no dry season (Dfa).

Both are in or near the cool temperate moist forest biome.

The annual mean temperature is 2.9 °C (5.2°F) warmer.

Average monthly temperatures vary by 6.6 °C (11.9°F) less in Wilmington Porter Reservoir, De. The continentality subtype is subcontinental as opposed to truly continental.

Total annual precipitation averages 392.7 mm (15.5 in) more which is equivalent to 392.7 l/m² (9.64 US gal/ft²) or 3,927,000 l/ha (419,822 US gal/ac) more. About 1 1/2 as much.

The altitude of the sun at midday is overall 3° higher in Wilmington Porter Reservoir, De than in Prairie Du Chien, Wi.